The present invention relates to automotive vehicles in general, and more particularly to improvements in automotive vehicles of the type wherein the clutch between a rotary part (e.g., the crankshaft) of the engine and a rotary part, (e.g., the input shaft) of the change-speed transmission is automatically disengaged to interrupt the power flow between the two rotary parts in response to actuation of the gear-shift, and wherein the clutch is automatically reengaged in response to termination of actuation of the gear-shift.
It is already known to automatically disengage the clutch of an automotive vehicle in response to actuation of the gear-shift, e.g., in response to establishment of bodily contact between the gear-shift lever and the driver of the vehicle, and to automatically reengage the clutch as soon as the actuation of the gear-shift is completed, i.e., as soon as the operator of the vehicle has selected a different speed ratio and his or her hand releases the gear-shift lever. Vehicles which embody the just discussed feature exhibit several important advantages in comparison with conventional vehicles wherein the operator must depress a clutch pedal prior to shifting into a different gear. Thus, the provision of an automatic (automatically engageable and disengageable) clutch simplifies the operation of the vehicle because the clutch pedal and its manipulation can be dispensed with. A vehicle which embodies an automatic clutch also exhibits several important advantages over vehicles with automatic transmissions, i.e., the utilization of an automatic or automated clutch eliminates transmission losses which arise during transmission of power by way of a hydrodynamic transducer of the type normally required in vehicles employing automatic transmissions.
However, presently known vehicles which employ automatic clutches also exhibit certain drawbacks, especially as regards the regulation of fuel admission during shifting from a first into a different second speed ratio. Thus, the operator of the vehicle must actuate the gas pedal in order to regulate the admission of fuel preparatory to and during actuation of the gear-shift. This is necessary in order to achieve a certain correspondence or optimum relationship between the RPM of the engine and the RPM of the input shaft of the change-speed transmission; such relationship determines the degree of smoothness with which the gear-ratio changing operation is carried out. If the RPM of the engine is not properly synchronized with the RPM of the input shaft of the change-speed transmission, excessive acceleration of the engine at the time of disengagement of the clutch (i.e., excessive depression of the gas pedal at the instant of beginning to actuate the gear-shift), is likely to raise the RPM of the engine to such an extent that the engine overspeeds as soon as the crankshaft is disconnected from the input shaft of the transmission. Inversely, if the gas pedal is released prematurely, the engine is likely to stall or the output shaft of the transmission is likely to undergo excessive and abrupt deceleration with resulting discomfort to the occupant or occupants of the vehicle.